Hair

Distribution by Scientific Domains

Kinds of Hair

  • anagen hair
  • black hair
  • body hair
  • cat hair
  • curly hair
  • facial hair
  • frey hair
  • glandular hair
  • human hair
  • long hair
  • pubic hair
  • red hair
  • root hair
  • scalp hair
  • short hair
  • terminal hair
  • unwanted hair
  • von frey hair
  • white hair

  • Terms modified by Hair

  • hair analysis
  • hair breakage
  • hair bulb
  • hair cell
  • hair cell function
  • hair cell loss
  • hair coat
  • hair color
  • hair colour
  • hair count
  • hair cycle
  • hair density
  • hair development
  • hair disease
  • hair disorders
  • hair dye
  • hair dyeing
  • hair fibre
  • hair follicle
  • hair follicle development
  • hair follicle stem cell
  • hair growth
  • hair length
  • hair loss
  • hair pigmentation
  • hair reduction
  • hair regrowth
  • hair removal
  • hair sample
  • hair shaft
  • hair shedding
  • hair sheep
  • hair surface
  • hair transplantation
  • hair treatment
  • hair type

  • Selected Abstracts


    CHANGES IN THE METAL CONTENT OF HUMAN HAIR DURING DIAGENESIS FROM 500 YEARS, EXPOSURE TO GLACIAL AND AQUEOUS ENVIRONMENTS

    ARCHAEOMETRY, Issue 3 2010
    I. M. KEMPSON
    Scanning electron microscopy, inductively coupled plasma mass spectroscopy and time-of-flight secondary ion mass spectrometry have been used to examine the extent and possible mechanisms by which the metal content of human hair is altered by exposure to aqueous environments. The results, using both modern hair and samples from 500-year-old hair associated with glacier-entombed remains, show that the metal content has been altered sufficiently so that the interpretation of the metal signature in terms of diet or disease is problematic. While endogenous information is difficult to glean from these data, interesting observations have been made of possible early stages of mineral authigenic deposition. The chemistry of the outer hair surface was found to be consistent with deposition of Fe and Al silicates, as well as other mineral phases. The ancient hair was analysed at the root region and included a comparison of the internal versus external composition to assist in identifying the diagenetic processes. [source]


    Photoepilation Results of Axillary Hair in Dark-Skinned Patients by IPL: A Comparison Between Different Wavelength and Pulse Width

    DERMATOLOGIC SURGERY, Issue 2 2006
    JONG HEE LEE MD
    BACKGROUND Recently, intense pulsed light (IPL) sources have been shown to provide long-term hair removal. OBJECTIVE This study examined the photoepilatory effects of different wavelengths and pulse width application in the same device and compared their efficiencies in Asian skin. METHODS Twenty-eight Korean women were treated using HR (600,950 nm filter) and 27 using HR-D (645,950 nm filter) in the axillar area. Four treatments were carried out at intervals of 4 to 6 weeks; follow-ups were conducted 8 months after the last treatment. Mean energy settings were 14.9±2.0 J/cm2 for HR and 17.1±0.6 J/cm2 for HR-D. Longer pulse widths were applied in case of HR-D treatment. Hair counts and photographic evaluation of skin sites were made at baseline and at the last follow-up. Final overall evaluations were performed by patients and clinicians. RESULTS Average clearances of 52.8% and 83.4% were achieved by HR and HR-D, respectively. No significant adverse effects were reported after HR-D treatment. One case each of hypopigmentation and hyperpigmentation was reported for HR. CONCLUSION An IPL source by removing 45 nm of the emitted spectra and applying longer pulse width was found to provide a safer and more effective means of photoepilation in Asian patients. [source]


    Hair, Human Evolution, and the Idea of Human Uniqueness

    EVOLUTIONARY ANTHROPOLOGY, Issue 4 2005
    Niccolo Caldararo
    No abstract is available for this article. [source]


    Causes of hair loss and the developments in hair rejuvenation

    INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 1 2002
    D. H. Rushton
    Synopsis Hair is considered to be a major component of an individual's general appearance. The psychological impact of hair loss results in a measurably detrimental change in self-esteem and is associated with images of reduced worth. It is not surprising that both men and women find hair loss a stressful experience. Genetic hair loss is the major problem affecting men and by the age of 50, up to 50% will be affected. Initial attempts to regenerate the lost hair have centred on applying a topical solution of between 2% to 5% minoxidil; however, the results proved disappointing. Recently, finasteride, a type II 5, reductase inhibitor has been found to regrow a noticeable amount of hair in about 40% of balding men. Further developments in treatments have lead to the use of a dual type I and type II inhibitor where 90% of those treated regrow a noticeable amount of hair. In women the major cause of hair loss before the age of 50 is nutritional, with 30% affected. Increased and persistent hair shedding (chronic telogen effluvium) and reduced hair volume are the principle changes occurring. The main cause appears to be depleted iron stores, compromised by a suboptimal intake of the essential amino acid l -lysine. Correction of these imbalances stops the excessive hair loss and returns the hair back to its former glory. However, it can take many months to redress the situation. Résumé Les cheveux sont considérés comme étant une composante majeure de l'aspect général d'un individu. L'impact psychologique de la perte des cheveux conduit à une diminution mesurable de l'estime de soi et s'associe à des images de contexte négatif. Il n'est pas surprenant que les hommes comme les femmes ressentent la perte de cheveux comme une expérience stressante. La perte génétique des cheveux est le problème principal qui touche les hommes et autour de l'âge de 50 ans, jusqu'à 50% seront concernés. Les premières tentatives de régénération des cheveux perdus se sont focalisées sur l'application topique d'une solution comprenant entre 2% et 5% de minoxidil; cependant, les résultats se sont avérés décevants. Récemment, le finastéride, un inhibiteur de la 5,-réductase de type II s'est avéré permettre la repousse d'une quantité significative de cheveux chez environ 40% des hommes dégarnis. Les développements ultérieurs des traitements ont conduit à l'utilisation d'un inhibiteur associant type I et type II pour lequel 90% des personnes traitées constatent une repousse significative des cheveux. Chez les femmes la cause principale de la perte des cheveux avant l'âge de 50 ans est d'origine nutritionnelle, avec 30% de la population affectée. Une perte de cheveux persistante et croissante (telogen effluvium chronique) et un volume des cheveux réduit sont les principaux effets qui se produisent. La cause principale semble être des réserves de fer épuisées, associées à une prise insuffisante de l'acide aminé essentiel L-lysine. La correction de ces déséquilibres stoppe la perte excessive de cheveux et rend aux cheveux leur éclat d'antan. Cependant, plusieurs mois peuvent être nécessaires pour redresser la situation. [source]


    Efficacy of chemical and botanical over-the-counter pediculicides available in Brazil, and off-label treatments, against head lice ex vivo

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 3 2010
    André Asenov MD
    Background, There is a lack of reliable data on the efficacy of over-the-counter (OTC) pediculicides in Brazil. Methods, We performed ex vivo assays of eight marketed pediculicides: 1% permethrin (Kwell®, Clean Hair®, Keltrina®, Nedax®), 0.02% deltamethrin (Deltacid®, Pediderm®), and two "natural" products (Piolho e Lêndea®, Pilogenio®). We also tested 5% permethrin (Keltrina Plus®), traditional home remedies and an ivermectin-based product used in veterinary medicine. Head lice (49,52 per group) were immersed in the compound for 3 min and washed after 20 min to simulate the typical in vivo treatment protocol. Lice were examined for activity up to 24 h using stringent criteria for survival. Results, Of the permethrin containing products, highest mortality was observed with Kwell® and Clean Hair® (97.9 and 90.2% after 4 h). Keltrina®, Nedax®, Keltrina Plus®, and the two deltamethrin-based products showed only a low efficacy of <60% after 4 h. With exception of pure coconut oil (80% mortality after 4 h), home remedies showed a very low efficacy, and both marketed products killed few lice. The ivermectin-based product caused a mortality of 100% after 4 h. Conclusions, Most Brazilian OTC products did not show a satisfactory efficacy against head lice. Resistance may be present. Ivermectin and coconut oil are promising compounds for topical treatment. Laboratory-based tests should be used to assess resistance patterns and to identify formulations of the active ingredient that increase the efficacy. Standardized testing should be performed before a product is licensed for head lice treatment. [source]


    Hair colouring, permanent styling and hair structure

    JOURNAL OF COSMETIC DERMATOLOGY, Issue 3-4 2003
    S Harrison
    Summary Hair is an important component of body image and has immense psychological importance for both men and women. Women, in particular, over the ages have modified their appearance through changing their hair colour or style. Hair can be straight, wavy or curly, blonde, black, brown or red. These natural variations are an important part of our identity that can be manipulated according to the dictates of fashion, culture or society. Different types of hair have varying affinity for the different colouring and waving methods. Damaged hair also has a different affinity for hair products than normal healthy hair. The hair shaft is remarkably strong and resistant to the extremes of nature. Hair cosmetics are widely available and manipulate the structural properties of hair. Whilst most procedures are safe, there is considerable potential for damage to the hair and hair problems of acute onset, including hair breakage, hair loss and loss of condition, are frequently blamed on the last product used on the hair. Hair problems are particularly prevalent among people who repeatedly alter the natural style of their hair. [source]


    Trichophyton Mentagrophytes Perforates Hair of Adult Corpses in the Gaseous Period,

    JOURNAL OF FORENSIC SCIENCES, Issue 5 2010
    Renato Evando M. Filho M.S
    Abstract:, Despite the substantial literature on mycology, there are still limited reports of the interaction between fungi and human hosts in the postmortem period. Thus, the main goal of this study was to investigate the in vitro perforation test using Trichophyton mentagrophytes on hair from adult corpses in the postmortem period (gaseous period). The protocol was carried out with positive (prepubescent children's hair) and negative controls (healthy adult hair) as well. One strain of Trichophyton rubrum was also used as a negative perforation control. Perforations were found in all the hair samples from corpses and prepubescent children after 12,14 days exposure to T. mentagrophytes and were absent in the hair samples of healthy adults. Furthermore, hair perforation was not observed with T. rubrum. Our preliminary findings suggest the use of T. mentagrophytes as a potential marker of the death interval in forensic science. [source]


    Heteroplasmy in Hair: Study of Mitochondrial DNA Third Hypervariable Region in Hair and Blood Samples,

    JOURNAL OF FORENSIC SCIENCES, Issue 3 2010
    Greiciane G. Paneto M.Sc.
    Abstract:, Mitochondrial DNA (mtDNA) analysis has proved useful for forensic identification especially in cases where nuclear DNA is not available, such as with hair evidence. Heteroplasmy, the presence of more than one type of mtDNA in one individual, is a common situation often reported in the first and second mtDNA hypervariable regions (HV1/HV2), particularly in hair samples. However, there is no data about heteroplasmy frequency in the third mtDNA hypervariable region (HV3). To investigate possible heteroplasmy hotspots, HV3 from hair and blood samples of 100 individuals were sequenced and compared. No point heteroplasmy was observed, but length heteroplasmy was, both in C-stretch and CA repeat. To observe which CA "alleles" were present in each tissue, PCR products were cloned and re-sequenced. However, no variation among CA alleles was observed. Regarding forensic practice, we conclude that point heteroplasmy in HV3 is not as frequent as in the HV1/HV2. [source]


    Investigation of dyed human hair fibres using apertureless near-field scanning optical microscopy

    JOURNAL OF MICROSCOPY, Issue 2 2006
    F. FORMANEK
    Summary We present the first studies of dyed human hair fibres performed with an apertureless scanning near-field optical microscope. Samples consisted of 5-µm-thick cross-sections, the hair fibres being bleached and then dyed before being cut. Hair dyed with two molecular probes diffusing deep inside the fibre or mainly spreading at its periphery were investigated at a wavelength of 655 nm. An optical resolution of about 50 nm was achieved, well below the diffraction limit; the images exhibited different optical contrasts in the cuticle region, depending on the nature of the dye. Our results suggest that the dye that remains confined at the hair periphery is mainly located at its surface and in the endocuticle. [source]


    Feeding and survival of Culicoides sonorensis on cattle treated with permethrin or pirimiphos-methyl

    MEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2000
    B. A. Mullens
    Summary The persistence of permethrin (5% a.i.) and pirimiphos-methyl (27% a.i.), applied to the dorsum of calves in the field against Culicoides sonorensis Wirth and Jones (Diptera: Ceratopogonidae), was estimated using a hair-blood-feeding bioassay in the laboratory. Hair clippings were taken before treatment and 3, 7, 14, 21, 28, 42 and 56 days after treatment from the dorsum, side and belly of treated and control calves. Laboratory-reared insects were allowed to feed through thin hair layers and a parafilm membrane on sheep blood warmed using a water-jacketed feeder. Some intoxication after exposure to hair was noted up to 28 days after treatment with permethrin and up to 14 days after treatment with pirimiphos-methyl. Hair from the dorsum caused more intoxication for a longer period than hair from other body regions. Permethrin and pirimiphos-methyl applied to the back did not significantly reduce overall engorgement (body regions pooled) after treatment. Permethrin residues on hair remained far higher on the back than other body regions and were related to insect intoxication and reduction in engorgement in the laboratory. Residues on belly hair never exceeded 12 p.p.m. and did not result in significantly reduced feeding at any time. Engorged insects that exhibited sublethal intoxication from feeding through permethrin-treated hair did recover and matured numbers of eggs comparable to controls. Field trials using treated and control calves and enclosure nets showed that dorsal applications of 5% permethrin were not effective in reducing engorgement, despite some intoxication. Vacuum samples from a calf showed that C. sonorensis fed primarily on the belly. A 0.2% permethrin application on the belly (250 ml) did result in >,80% reduction of C. sonorensis in the enclosure nets at 3 and 7 days after treatment, but activity had subsided by 10 days after treatment. The utility of insecticidal treatments for suppression of this vector is discussed. [source]


    Pedunculated Lesion of the Scalp with Surrounding Long, Dark Hair in a Newborn

    PEDIATRIC DERMATOLOGY, Issue 5 2010
    Almudena Hernández-Núñez M.D.
    No abstract is available for this article. [source]


    A Girl with Loose Anagen Hair Syndrome and Uncombable, Spun-glass Hair

    PEDIATRIC DERMATOLOGY, Issue 3 2005
    Abigail J. Lee MC
    A hair pull test revealed that hairs could be easily and painlessly extracted. Light microscopic examination of the hair demonstrated anagen hairs with a ruffled cuticle and distorted bulb as well as an unusual undulation and grooving of the shafts. These findings are consistent with both loose anagen and uncombable hair syndromes. The occurrence of both syndromes in the same patient seems unlikely, and we propose that our patient has loose anagen hair syndrome with features resembling uncombable hair syndrome. [source]


    Acquired Progressive Kinking of the Hair

    PEDIATRIC DERMATOLOGY, Issue 3 2004
    Susan B. Mallory M.D.
    First page of article [source]


    Near Infrared Spectroscopy as a Tool for the Determination of Eumelanin in Human Hair

    PIGMENT CELL & MELANOMA RESEARCH, Issue 4 2004
    Marina Zoccola
    Eumelanins are brown-black pigments present in the hair and in the epidermis which are acknowledged as protection factors against cell damage caused by ultraviolet radiation. The quantity of eumelanin present in hair has recently been put forward as a means of identifying subjects with a higher risk of skin tumours. For epidemiological studies, chromatographic methods of determining pyrrole-2,3,5-tricarboxylic acid (PTCA; the principal marker of eumelanin) are long, laborious and unsuitable for screening large populations. We suggest near infrared (NIR) spectroscopy as an alternative method of analysing eumelanin in hair samples. PCTA was determined on 93 samples of hair by means of oxidizing with hydrogen peroxide in a basic environment followed by chromatographic separation. The same 93 samples were then subjected to NIR spectrophotometric analysis. The spectra were obtained in reflectance mode on hair samples which had not undergone any preliminary treatment, but had simply been pressed and placed on the measuring window of the spectrophotometer. The PTCA values obtained by means of HPLC were correlated with the near infrared spectrum of the respective samples. A correlation between the PTCA values obtained by means of HPLC and the PTCA values obtained from an analysis of the spectra was obtained using the principal component regression (PCR) algorithm. The correlation obtained has a coefficient of regression (R2) of 0.89 and a standard error of prediction (SEP) of 13.8 for a mean value of 108.6 ng PTCA/mg hair. Some considerations about the accuracy of the obtained correlation and the main sources of error are made and some validation results are shown. [source]


    Using carbon isotopes to track dietary change in modern, historical, and ancient primates

    AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2009
    Matt Sponheimer
    Abstract Stable isotope analysis can be used to document dietary changes within the lifetimes of individuals and may prove useful for investigating fallback food consumption in modern, historical, and ancient primates. Feces, hair, and enamel are all suitable materials for such analysis, and each has its own benefits and limitations. Feces provide highly resolved temporal dietary data, but are generally limited to providing dietary information about modern individuals and require labor-intensive sample collection and analysis. Hair provides less well-resolved data, but has the advantage that one or a few hair strands can provide evidence of dietary change over months or years. Hair is also available in museum collections, making it possible to investigate the diets of historical specimens. Enamel provides the poorest temporal resolution of these materials, but is often preserved for millions of years, allowing examination of dietary change in deep time. We briefly discuss the use of carbon isotope data as it pertains to recent thinking about fallback food consumption in ancient hominins and suggest that we may need to rethink the functional significance of the australopith masticatory package. Am J Phys Anthropol 140:661,670, 2009. © 2009 Wiley-Liss, Inc. [source]


    Titelbild: Determination of Arsenic Poisoning and Metabolism in Hair by Synchrotron Radiation: The Case of Phar Lap (Angew. Chem.

    ANGEWANDTE CHEMIE, Issue 25 2010
    25/2010)
    Nach achtzig Jahren hat eine Obduktion das Geheimnis um den Tod des berühmten Rennpferds Phar Lap gelüftet. I. Kempson und D. Henry beschreiben in ihrer Zuschrift auf S.,4333,ff. auffällige Arsenverteilungen und -verbindungen, die darauf hindeuten, dass Phar Lap das Gift Stunden vor seinem unerwarteten qualvollen Ende eingenommen hat. Diese außergewöhnliche Haaranalyse beleuchtet metabolische Prozesse nach der Arsenaufnahme. [source]


    Determination of Arsenic Poisoning and Metabolism in Hair by Synchrotron Radiation: The Case of Phar Lap,

    ANGEWANDTE CHEMIE, Issue 25 2010

    Neues Beweismaterial zum Tod des Rennpferds Phar Lap (siehe Photo) lieferten hochauflösende Röntgen-Fluoreszenz(XRF)- und Röntgen-Nahkantenabsorptions(XANES)-Analysen von Mähnenhaaren mithilfe von Synchrotronstrahlung. Die Ergebnisse deuten auf Arsenaufnahme und -metabolismus hin , das Rennpferd erlag folglich einer Vergiftung. [source]


    Dermoscopy of Hair and Scalp Disorders: With Clinical and Pathological Correlations

    AUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 4 2009
    Alex Chamberlain
    No abstract is available for this article. [source]


    Method validation for measurement of hair nicotine level in nonsmokers

    BIOMEDICAL CHROMATOGRAPHY, Issue 3 2009
    Sung Roul Kim
    Abstract The development of strategies to address the growing worldwide burden of exposure to secondhand smoke (SHS) would be facilitated by sensitive and accurate methods for assessing SHS exposure. Hair provides a readily available matrix for assessing biomarkers of typical SHS exposure. We developed and applied an optimized analytical method using an isotope dilution gas chromatography,mass spectrometry (GC/MS) for hair nicotine measurement. The utility of this optimized method is illustrated by presenting data on SHS exposure of women and children from 31 countries. Using this isotope dilution method with spiked samples (3.3 ng/mg), we found that the greatest hair nicotine extraction efficiency was obtained with a 60 min shaking time. In the field study (n = 2400), a positive association was evident between hair nicotine concentrations from nonsmokers and higher numbers of cigarettes smoked per day in a household. Copyright © 2008 John Wiley & Sons, Ltd. [source]


    A Place Where I Can Let My Hair Down: from social club to cultural center in an urban Indian community

    CITY & SOCIETY, Issue 1 2001
    Deborah Davis Jackson
    The "Riverton" Indian Center was established in the 1950s as large numbers of Native Americans migrated to the city from reservations around the Great Lakes and beyond, and underwent significant changes throughout the second half of the twentieth century. These changes, and the conflicts that resulted from them, were shaped by far larger political,economic and cultural forces: on the one hand, River ton's economy, along with the economies of many midsized cities in the Great Lakes region,was undergoing rapid deindustrialization with devastating consequences to local residents, including American Indians; on the other hand, social and cultural changes in the U.S., starting in the 1960s, made Native Americans,or at least a romanticized image of Native Americans,increasingly popular with non-Natives. These forces converged to create the three distinct phases in the Riverton Indian Center's history, each associated with a particular age cohort,a trajectory that might well be typical of deindustrializing cities in the Great Lakes region. [American Indians; community and identity; deindistrialivng cities; Upper Great Lakes region] [source]


    Degeneration of Nuclei and Mitochondria in Human Hairs

    JOURNAL OF FORENSIC SCIENCES, Issue 2 2009
    Charles A. Linch B.S.
    Abstract:, It is generally accepted that nuclei degrade in developing hair shafts but the point at which such occurs has not been investigated. The fate of mitochondria in the keratinizing hair shaft has been less clear. This study uses transmission electron microscopy to investigate when nuclei and mitochondria are no longer visible in the developing hair shaft. Serial sections were obtained from anagen head hairs absent follicles in order to determine the sequence of degradation of nuclei and mitochondria in the hair shaft by starting at the root bulb and proceeding toward the hair tip. It was demonstrated that nuclei and mitochondria become invisible in the keratinizing hair shaft at about the same time. This was found to occur fairly early in the process at the level of the hair shaft where the hair cuticle becomes permanent. [source]


    Using particles for 3D texture sculpting

    COMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 4 2001
    ich Bene
    Abstract Particle systems have been used in computer graphics for many different purposes, including visual simulation of fur, grass, hair, and similar fuzzy textures and shapes. The underlying theories used in these algorithms are usually quite complex and are mostly based on simulation of diffuse-limited aggregation, cellular development, reaction-diffusion models, etc. This leads to high time complexity of these algorithms. The purpose of this paper is to show that collision detection and distance keeping among moving particles can generate similar realistic textures efficiently. This approach is easy to implement, sufficiently fast allowing for interactive modeling, and inherits the major features from the previously published techniques. We first construct a scene consisting of generators of particles, attractors, and cutters. The generators generate oriented particles, and the attractors attract or repulse them. When collision with the cutter is detected, the particle performs an action according to its state and position in the 3D space. Every particle has assigned a table of possible actions that is used for solving these critical states. Trajectories of the particles are then used as a resulting shape of the texture. Copyright © 2001 John Wiley & Sons, Ltd. [source]


    Movie Making at Pixar: A Collaboration of Art and Technology

    COMPUTER GRAPHICS FORUM, Issue 3 2005
    Rob Cook
    This talk takes you behind the scenes at Pixar Animation Studios for an in-depth look at how its 3d computer graphics films are made. Making a computer animated film involves people with artistic talent and people with technical skills working together in close collaboration. The process starts with the development of the story and continues with modeling the geometry, adding articulation controls, using those controls to animate the characters, simulating things like water and cloth and hair, defining the look of the surfaces, putting lights in the scene, adding special effects, rendering, and post-production. Special emphasis is given to the roles of technology and computer graphics research in supporting the filmmaker. [source]


    Epidemiological data on consumer allergy to p -phenylenediamine

    CONTACT DERMATITIS, Issue 6 2008
    Jacob Pontoppidan Thyssen
    Many women and men now dye their hair. p-Phenylenediamine (PPD) is a frequent and important component of permanent hair dye products; exposure to it may cause allergic contact sensitization, acute dermatitis, and severe facial oedema. To increase our understanding of PPD allergy, we reviewed published literature containing PPD patch test data from dermatitis patients and individuals in the general population. This was performed to estimate the median prevalence and the weighted average of PPD sensitization and thereby assess the burden of PPD-containing hair care products on health. Literature was examined using PubMed,MEDLINE, Biosis, and Science Citation Index. The median prevalence among dermatitis patients was 4.3% in Asia, 4% in Europe, and 6.2% in North America. A widespread increase in the prevalence of PPD sensitization was observed among Asian dermatitis patients. In Europe, a decrease in the 1970s was replaced by a plateau with steady, high prevalences ranging between 2% and 6%. The prevalence remained high in North America, although a decreasing tendency was observed. Contact allergy to PPD is an important health issue for both women and men. More stringent regulation and enforcement are required as public health measures to reduce the burden of disease that exposure to PPD has brought to populations. [source]


    Allergic contact dermatitis from hair dye and development of lichen simplex chronicus

    CONTACT DERMATITIS, Issue 1 2004
    Won Young Chey
    Those who dye their hair frequently manifest allergic contact dermatitis (ACD) from p -phenylenediamine (PPD)-containing hair dye. PPD is known to be the most frequent sensitizer in hair dye, but there has been no documentation of this sensitizer having a role in chronic dermatologic conditions. Our department experienced a case of a 62-year-old woman with lichen simplex chronicus (LSC), who complained of aggravation after hair dyeing and made such an association. We conducted a prospective and retrospective study to further evaluate the clinical associations between the two. In our prospective study, patch testing was performed in selected patients who regularly carried out hair dyeing and also had clinical manifestations of LSC. Also a retrospective examination was conducted in cases where patch testing had been performed with PPD in the past for suspected ACD and further selected cases with concurrent LSC and/or other neurodermatitis. 11 and 14 patients in our prospective and retrospective study, respectively, presented with both LSC and positive findings to PPD. 5 (45.5%) and 4 (28.6%) patients in our prospective and retrospective study showed clinical relevance from clinical improvement after stopping use and rechallenge. We report several cases of patients diagnosed as having LSC and/or prurigo nodularis who showed clinical improvement after discontinuing the use of hair dye. The suggestion can therefore be made that hair dye could be a possible aetiologic agent causing LSC in those using hair dyes. [source]


    Hair dye contact allergy: quantitative exposure assessment of selected products and clinical cases

    CONTACT DERMATITIS, Issue 6 2004
    Heidi SØsted
    Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p -phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m -aminophenol (0.015 to 0.38%) and p -aminophenol (0.16 to 2.1%) were found in 3 products. The concentration levels were similar in the patient's products compared to a random sample of 16 hair dye products. The concentration present of toluene-2,5-diamine elicited allergic reactions in concentrations that were 10-fold lower than the legal EU limit of 10%. Hair dye allergy may cause severe clinical reactions, and the current regulation is insufficient in protection of the users. A preventive strategy is needed. [source]


    Paradoxical Hypertrichosis After Laser Therapy: A Review

    DERMATOLOGIC SURGERY, Issue 3 2010
    SHRADDHA DESAI MD
    BACKGROUND Laser hair removal is a safe and effective procedure for the treatment of unwanted body hair but is not exempt from side effects. A rare but significant adverse effect with this treatment modality is paradoxical hypertrichosis. OBJECTIVE To evaluate the potential etiologies, risk factors, related laser types, and treatment options for the development of excess hair after laser therapy. MATERIALS AND METHODS An analysis of previously published case studies and review articles along with our own experience was used to gather information regarding this phenomenon. RESULTS Paradoxical hypertrichosis has a low incidence, ranging from 0.6% to 10%, and most commonly occurs on the face and neck. All laser and light sources have the potential to cause hair induction, especially in individuals with darker skin types (III,VI); with dark, thick hair; and with underlying hormonal conditions. Possible causes include the effect of inflammatory mediators and subtherapeutic thermal injury causing induction of the hair cycle. Treatment for paradoxical hypertrichosis is laser therapy of the affected area. CONCLUSIONS Paradoxical hypertrichosis is a rare side effect of laser hair removal; the pathogenesis of this event remains widely unknown. We recommend further large-scale studies to investigate this effect. The authors have indicated no significant interest with commercial supporters. [source]


    Effects of Finasteride (1 mg) on Hair Transplant

    DERMATOLOGIC SURGERY, Issue 10 2005
    Matt Leavitt DO
    Background. The improved scalp coverage achieved by hair transplant for men with androgenetic alopecia can be diminished by continued miniaturization and loss of preexisting, nontransplanted hairs. Objectives. To evaluate whether finasteride 1 mg, administered daily from 4 weeks before until 48 weeks after hair transplant, improves scalp hair and growth of nontransplanted hair in areas surrounding the transplant and to evaluate the safety and tolerability of finasteride for men undergoing hair transplant. Methods. In this randomized, double-blind, placebo-controlled study, 79 men with androgenetic alopecia (20,45 years of age) were assigned to treatment with finasteride 1 mg (n = 40) or placebo (n = 39) once daily from 4 weeks before until 48 weeks after hair transplant. Efficacy was evaluated by review of global photographs by an expert dermatologist and by macrophotography for scalp hair counts. Results. Treatment with finasteride resulted in significant improvements from baseline, compared with placebo, in scalp hair based on global photographic assessment (p < .01) and hair counts (p < .01) at week 48. Visible increases in superior/frontal scalp hair post-transplant were recorded for 94% and 67% of patients in the finasteride and placebo groups, respectively. Finasteride treatment was generally well tolerated. Conclusion. For men with androgenetic alopecia, therapy with finasteride 1 mg daily from 4 weeks before until 48 weeks after hair transplant improves scalp hair surrounding the hair transplant and increases hair density. [source]


    Hair Growth Induced by Diode Laser Treatment

    DERMATOLOGIC SURGERY, Issue 5 2005
    Eric F. Bernstein MD
    background. Although hair reduction by long-pulsed red and infrared lasers and light sources is generally quite effective, paradoxical hair growth has rarely been observed following treatment. objective. To report a case of thick hair growth following 810 nm diode laser treatment and its subsequent treatment. methods. A 24-year-old man who had previously had laser hair reduction on his posterior neck was treated to a test area on his upper back. results. Thick terminal hair developed in the treated area subsequent to laser treatment. Further treatment of this area removed the terminal hair but resulted in terminal hair growth in an annular distribution surrounding the treatment site. conclusions. Diode laser treatment rarely stimulates terminal hair growth. This phenomenon should be studied to better understand hair growth cycles and to help develop more effective treatments for hair loss and hair growth. [source]


    Pilonidal Sinus Disease Treated by Depilation Using an 800 nm Diode Laser and Review of the Literature

    DERMATOLOGIC SURGERY, Issue 5 2005
    Anthony V. Benedetto DO, FACP
    background. Pilonidal sinus disease is a debilitating, disfiguring chronic ailment that is often resistant to therapy. Its etiology and treatment remain in question. objective. To assess the efficacy of an 800 nm diode laser in the treatment of recalcitrant pilonidal sinus disease. methods. Two patients with recalcitrant pilonidal sinus disease were treated in the lower back, buttocks, and perigluteal cleft area with an 800 nm diode laser with a spot size of 9 × 9 mm, fluences of 30 to 48 J/cm2, and pulse widths of 15 to 24 milliseconds. results. Long-term relief of pilonidal sinus disease was produced with as few as two treatments 2 months apart to as many as six treatments over a 2-year period. With each successive treatment, fewer pulses were needed and the interval between treatments increased. conclusion. The 800 nm diode laser may be an effective tool in the treatment of pilonidal sinus disease. By eliminating the source of hair and hair fragments that course along the surface of the lower back and buttocks, interruption of the etiologic source for pilonidal sinus disease can be accomplished. [source]